A rare case of esophageal adenocarcinoma with urinary bladder metastasis.

A 75-year-old man was admitted to our hospital for treatment of esophageal cancer (EC) in March 2017. Esophagogastroduodenoscopy revealed Barrett's esophagus and superficial, distal EC (type 0-IIc). Tumor biopsy showed esophageal adenocarcinoma. Computed tomography revealed no lymph node metastasis but did reveal a 19-mm tumor on the right side of the urinary bladder. Bladder cancer (BC) was also suspected, and the patient underwent endoscopic submucosal dissection for EC and transurethral resection of the bladder tumor. The pathological diagnosis of EC was moderately to poorly differentiated adenocarcinoma (tub2), pT1b (SM), ly0, v0. The pathological horizontal margin was negative and the vertical margin was positive. Additional esophagectomy and lymph node dissection were indicated for curability. Esophagectomy was difficult because the patient had severe cardiovascular disease, so follow-up observation was adopted. BC was classified as urothelial carcinoma Ta, ly0, v0. After 32 months, multiple tumors were found in the bladder, and BC recurrence was suspected. Transurethral resection of the bladder was performed again for seven tumors, and pathological diagnosis was poorly differentiated adenocarcinoma (tub2). The immunohistochemical features matched those of EC. We diagnosed EC metastasis in the urinary bladder. Bladder adenocarcinoma is difficult to distinguish from metastasis from other organs, especially the upper gastrointestinal tract, and cytomorphological features and appropriate clinical history are required. © The Japan Society of Clinical Oncology 2020.